Re: Block-level CRC checks

Jonah H. Harris wrote:
> On Thu, Oct 2, 2008 at 1:07 PM, Bruce Momjian <bruce@momjian.us> wrote:
> >> If we're double-buffering the write, I don't see where we could be
> >> introducing a torn-page, as we'd actually be writing a copied version
> >> of the buffer.  Will look into this.
> >
> > The torn page is during kernel write to disk, I assume, so it is still
> > possible.
> 
> Well, we can't really control too much of that.  The most common
> solution to that I've seen is to double-write the page (which some
> OSes already do regardless).  Or, are you meaning something else?

I just don't see how writing a copy of the page (rather than the
original) to the kernel affects issues about torn pages.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +